1. Field of the Invention
The present invention relates to a knitted band for a zipper, and in particular relates to a knitted band having a convex portion on one side to join the zipper to enhance strength.
2. Description of the Related Art
Accordingly, a zipper comprises a pair of bands, a pair of teeth strips fixed to the band and a head engaging or releasing the teeth strips. The bands are stitched to cloth, hand bags or luggage box.
When a zipper is used, traverse force is exerted on the zipper, especially for the zipper on a hand bag or a luggage box. The teeth strips are made of material of high strength, such as Nylon or copper. The junction of the teeth strips and the knitted bands is the most weak point of the zipper. It is easily damaged by large traverse force.
To improve the strength of the junction of the teeth strips and the bands, reinforce threads having a diameter large than the threads of the band are used. In such a structure, although the strength is increased, the reinforce thread cannot be completely knitted with other threads of the bands, which causes uneven surface of the band resulting in unsmooth running of the head.